In restaurants today, it is common to offer regular coffee and caffeine-free coffee (Sanka). The waiter or waitress typically walks around to the tables and offers patrons coffee from one of two pots - one for regular and one for caffeine-free. This procedure requires that the waiter or waitress use both hands to carry the pots. This procedure is quite cumbersome and can even be dangerous.
Typically the pots are of a spherical shape and are made of glass. It is reported that these glass pots have an average service life of about two months.
Heretofore, vessels have been designed to selectively dispense one of two liquids carried by the vessels. See for example:
Swiss patent No. 179,021, issued Nov. 1, 1935; PA1 U.S. Pat. No. 795,408, issued July 25, 1905; PA1 U.S. Pat. No. 1,312,203, issued Aug. 5, 1919; PA1 U.S. Pat. No. 1,419,515, issued June 13, 1922; PA1 U.S. Pat. No. 1,472,007, issued Oct. 23, 1923; PA1 U.S. Pat. No. 2,604,233, issued July 22, 1952. PA1 U.S. Pat. No. 2,681,745, issued June 26, 1954;
British specification No. 19,809, published Aug. 27, 1908, discloses a multiliquid vessel for coffee and milk, which can be dispensed simultaneously. The dispenser actuator is mounted near the handle so that the person holding the pot by the handle can use his or her thumb to actuate the dispensing of coffee and milk simultaneously as the dispenser is tipped for pouring.
Condiment holders for granulated solids, such as salt and pepper, have also been devised for selectively dispensing one of the solids. See, for example, the U.S. Pat. Nos. to Clemmer 956,942, issued May 3, 1910, and Lacy 982,371, issued Jan. 24, 1911.
All of the foregoing dispensers are not readily adaptable to the modern spherical coffeepots which are used in today's restaurants. Further, the dispensers all appear relatively complex and expensive to manufacture.
It is also known to make spherical coffeepots with a stainless steel bottom portion and a polysulfone injection-molded plastic top portion. See, for example, Union Carbide publication entitled "Designing for Performance, Not For Value" dated Nov. 9, 1980.